1. Field of the Invention
The present invention relates to a pickup adjusting mechanism for a disc player, which is enabled to adjust the tilt angle of the pickup capable of laterally moving in an opening portion provided inside a chassis of a disc player.
2. Description of the Related Art
Hitherto, there has been a conventional adjusting mechanism for adjusting such a tilt angle, which is, for example, an optical head described in JP-A-8-171726.
As illustrated in FIGS. 2A, 2B, and 3, this optical head is equipped in an optical information recording/reproducing apparatus for optically recording information on, reproducing information from, or deleting information from an information recording medium surface. The optical head has an optical pickup actuator 109, and a carriage 110 for carrying the actuator 109. Further, a tapered surface 101 is provided on one of the actuator 109 and the carriage 110. A spherical portion 102 to be brought into sliding contact with the tapered surface 101 is provided in the other of the actuator 109 and the carriage 110. Thus, the optical head is adapted to adjust the inclination of the actuator 109 by putting the tapered surface 101 and the spherical portion 102 into sliding contact with each other. In this optical head, an adhesive agent 111 is applied onto the tapered surface 101 or the spherical portion 102. Thereafter, the inclination adjustment is performed by attaching the tapered surface 101 and the spherical portion 102 to each other. After the inclination adjustment, the actuator 109 is fixed to the carriage 110 by hardening the adhesive agent.
However, in this optical head, the tapered surface 101 and the spherical portion 102 are fastened to each other, because the adhesive agent hardens after the inclination adjustment thereof. Thus, this conventional optical head has a drawback in that the inclination adjustment cannot be performed after the tapered surface 101 and the spherical portion 102 are fastened to each other. Moreover, this conventional optical head is configured so that the angle of the carriage 110 with respect to a rail 113 cannot be adjusted.
Further, JP-A-59-125730U describes a pickup adjusting mechanism for a disc player.
As illustrated in FIGS. 4 and 5, the disc player comprises a support device for rotating and driving a disc 204, a pickup 214a opposed to an information recording surface of the disc 204 at a predetermined distance, and a carriage 210 for supporting this pickup 214a and for moving the pickup 214a along the disc 204. In this disc player, a fulcrum screw 215 is attached to the carriage 210 in such a way as to be able to go up and down. A portion of the support member 213 for supporting the pickup 214a, which is provided right under the pickup, is supported at a tip end of this fulcrum screw 215. Adjusting screws 219a and 219b, which are positioned at a predetermined distance from the fulcrum screw 215, and other adjusting screws 221a and 221b positioned at a predetermined distance from the fulcrum screw 215 in a direction nearly perpendicular to a direction, in which the screws 219a and 219b are placed, are inserted into the carriage 210. All the tip ends of the adjusting screws 219a, 219b, 221a, and 221b are screwed into the support member 213.
However, this conventional mechanism has a drawback in that friction caused by the adjusting screws 219a, 219b, 221a, and 221b themselves is not taken into account at all.
Further, JP-A-61-149112U describes a conventional apparatus for adjusting an optical axis of a pickup in a CD player.
As shown in FIGS. 6A and 6B, a first chassis 305, to which pickup guide shafts 303a and 303b are attached, and a second chassis 310, to which a turntable 306 is attached in such a way as to be parallel with the first chassis 305, are provided in a CD player that needs the adjustment of inclination of an optical axis of a pickup 301. The first chassis 305 is inclined to the second chassis 310 by turning the first chassis 305 around the pickup guide shaft 303a or 303b serving as a fulcrum.
However, this conventional apparatus has a drawback in that the adjusting portion is not in contact with the chassis 305 and 310.
An object of the invention is to solve the drawbacks of the conventional apparatus, and to provide a pickup adjusting mechanism for a disc player, which enables a pickup to bring a secondary-shaft-side part into point contact with a chassis. The pickup has a tilt angle which is adjusted. The secondary shaft side part is opposed to a main-shaft-side part. As a result, the secondary-shaft-side part can laterally move, that reliability in holding the secondary-shaft-side part can be enhanced, and that the lateral movement of the pickup with respect to the chassis can be stably performed.
The invention is proposed to solve the aforementioned drawbacks. According to an aspect of the invention, there is provided a pickup adjusting mechanism (hereunder referred to as a first pickup adjusting mechanism of the invention) for a disc player, which comprises an inclined piece portion tilted frontwardly and obliquely downwardly in an opening portion inside a drive chassis and provided at a side opposite to a main shaft in a pickup adapted to laterally move by being guided at one side thereof by the main shaft, a screw for adjusting a tilt angle of the pickup, which is obliquely upwardly or downwardly screwed into the inclined piece portion so that a lower part thereof is placed at an inner part of the pickup, a flange-like holding portion that is provided in such a way as to be integral with the lower part of this screw and that has a sidewise-H-like section in a plan view thereof, and that is fitted to the opposite opening edge, so that the bottom surface edge of an upper flange portion abuts against a part of the top surface of the drive chassis, which is in the vicinity of the opening edge, and so that the bottom surface edge of this screw laterally moves by sliding along and being in contact with the part of the top surface, which is in the proximity of the opening edge, when the pickup laterally moves. In this mechanism, at least the bottom surface side portion of the peripheral edge of the upper flange-like portion of the flange-like holding portion is chamfered, so that an inner edge part of this chamfered portion laterally moves by sliding along and being in contact with the top surface placed in the vicinity of the opening edge. Moreover, the mounting angle xcex8 of the screw screwed into the pickup with respect to the drive chassis is set in such a way as to be larger than an adjusting amount of the tilt angle of the pickup.
According to another aspect of the invention, there is provided a pickup adjusting mechanism (hereunder referred to as a second pickup adjusting mechanism of the invention) for a disc player, which comprises an inclined piece portion tilted frontwardly and obliquely downwardly in an opening portion inside a drive chassis and provided at a side opposite to a main shaft in a pickup adapted to laterally move by being guided at one side thereof by the main shaft, a screw for adjusting a tilt angle of the pickup, which is obliquely upwardly or downwardly screwed into the inclined piece portion so that a lower part thereof is placed at an inner part of the pickup, a flange-like holding portion that is provided in such a way as to be integral with the lower part of this screw and that has a sidewise-H-like section in a plan view thereof, and that is fitted to the opposite opening edge, so that the bottom surface edge of an upper flange portion abuts against a part of the top surface of the drive chassis, which is in the vicinity of the opening edge, and so that the bottom surface edge of this screw laterally moves by sliding along and being in contact with the part of the top surface, which is in the proximity of the opening edge, when the pickup laterally moves.
According to an embodiment (hereunder referred to as a third pickup adjusting mechanism of the invention) of the second adjusting mechanism of the invention, at least the bottom surface side portion of the peripheral edge of the upper flange-like portion of the flange-like holding portion is chamfered, so that an inner edge part of the chamfered portion laterally moves by sliding along and being in contact with the top surface placed in the vicinity of the opening edge.
According to an embodiment (hereunder referred to as a fourth pickup adjusting mechanism of the invention) of the second adjusting mechanism of the invention, a mounting angle (xcex8) of the screw screwed into the pickup with respect to the drive chassis is set in such a way as to be larger than an adjusting amount of the tilt angle of the pickup.